#include <time.h>
#include <stdio.h>
#include <stdlib.h>

#define TAB_SIZE 7

void afficheTab(int tab[], int size);
int* fibonacci(int n);
void print_sizes();
void exercice_4();
int est_permutation(int* tab, int n);
int * permutation(int n);
char * appliquer_permutation(char * T, int * permutation, int n);

int main(int argc, char *argv[])
{
    /*int i;

    int *tab = fibonacci(TAB_SIZE);
    int * tabptr = tab;

    afficheTab(tab, TAB_SIZE);
    printf("\n\n");
    */
    //print_sizes();
    //exercice_4();

    // int tab[8] = {0, 1, 2, 3, 4, 5, 6, 7};
    // printf("%d\n", est_permutation(tab, 8));

    /*int * tab = permutation(TAB_SIZE);
    afficheTab(tab, TAB_SIZE);
    char bliat[TAB_SIZE] = "Bonjour";

    char * bliat_perm = appliquer_permutation(bliat, tab, TAB_SIZE);
    for (int i=0; i<TAB_SIZE; i++) {
        printf("%c", bliat_perm[i]);
    }
    printf("\n");

    free(bliat_perm);
    free(tab);*/

    return 0;
}

char * appliquer_permutation(char * T, int * permutation, int n) {
    int i;
    char * result = malloc(sizeof(char)*n);
    for (i=0; i<n; i++) {
        result[i] = T[permutation[i]];
    }
    return result;
}

int * permutation(int n) {
    int i, x1, x2, tmp;
    int * tab = malloc(sizeof(int)*n);
    for (i=0; i<n; i++) {
        tab[i]=i;
    }

    srand(time(NULL));

    for (i=0; i<n; i++) {
        x1 = rand()%n;
        x2 = rand()%n;
        tmp = tab[x1];
        tab[x1] = tab[x2];
        tab[x2] = tmp;
    }

    return tab;
}

int est_permutation(int* tab, int n) {
    int i;
    int* checked_tab = malloc(sizeof(int)*n);
    for (i=0; i<n; i++) {
        if(tab[i]<n && checked_tab[tab[i]]==0){
            checked_tab[tab[i]]=1;
        } else {
            return 0;
        }
    }
    free(checked_tab);
    return 1;
}

void afficheTab(int * tabptr, int size) {
    int i;

    if (tabptr==NULL) {
        return;
    }
    for (i=0; i<size; i++) {
        printf("%d, ", tabptr[i]);
    }
    printf("\n");
}

void exercice_4() {
    void * Z = malloc(10*4);
    int * X = Z;
    //afficheTab(X,10);
    //afficheTab((int *)((char *)X+8),8);
    free(Z);
}

int* fibonacci(int n) {
    int i;
    int* tab = malloc(sizeof(int)*n);
    tab[0] = 0;
    tab[1] = 1;
    
    for (i=2; i<n; i++) {
        tab[i]= tab[i-2] + tab[i-1];
    }

    return tab;
}

void print_sizes() {
    printf("char : %lu\n", sizeof(char));
    printf("int * : %lu\n", sizeof(int *));
    printf("int* : %lu\n", sizeof(int*));
    printf("void : %lu\n", sizeof(void));
    printf("void * : %lu\n", sizeof(void *));
    printf("long int : %lu\n", sizeof(long int));
    printf("long int * : %lu\n", sizeof(long int *));
}